1. Field of the Invention
The present invention relates generally to an air pump, and more particularly to a dispensing head of the air pump that is able to be quickly and firmly connected to any types of French valves.
2. The Prior Arts
FIG. 1 shows a connection of a conventional dispensing head 71 and a French valve 60 which includes a cylindrical portion having a first threaded section 61 and a second threaded section 62 located on the cylindrical portion with a narrowed neck connected between the first and second threaded sections 61, 62. An inlet valve 63 is connected on the second threaded section 62. The diameter of the first threaded section 61 is larger than the diameter of the second threaded section 62. The French valve 60 is used widely to bicycle tires. The dispensing head 71 includes a connection portion 711 which is threadedly connected to the first threaded section 61 so that the second threaded section 62 and the inlet valve 63 are located in the dispensing head 71. A seal member 712 is located within the dispensing head 71 and seals the connection between the first threaded section 61 and the connection portion 711. The air from the air pump is delivered into the inlet valve 63 of the tire via the dispensing head 71.
FIG. 2 shows an adaptor 80 that can be connected between the French valve 60 and an American valve 72. The adaptor 80 includes a connection passage 81 with which the second threaded section 62 of the French valve 60 is engaged. A space 82 is defined in an end of the adaptor 80 and communicates with the connection passage 81. A seal ring 83 is received in the space 82 and mounted onto the neck of the French valve 60 to prevent from air leakage.
The above-mentioned two dispensing head 71 and the adaptor 80 are invented by the applicant and welcomed in the market. However, another latest type of French valve 50 as shown in FIG. 3 is developed and the latest French valve 50 replaces the first threaded section 61 with a non-thread tube 51 and the second threaded section 52 and the inlet valve 53 are maintained. The latest French valve 50 can only be cooperated with the adaptor 80 mentioned above. Nevertheless, the adaptor is designed for connection with the American valve 72 and the latest French valve 50 has an advantage of larger air inlet volume feature, so that most of the users specially for racing bicyclers definitely choose the dispensing head that is designed for the French valve rather than the latest French valve 50 as shown in FIG. 3.